Ben Simmons said Tuesday his mental health struggles began well before the 76ers' season ended and he didn't believe he'd be able to overcome them in Philadelphia.

He's eager to begin moving on with the Brooklyn Nets, though isn't sure yet when he will join them on the court. Nor was he sure how things got so bad in Philadelphia.

“If I knew, I would tell you everything,” Simmons said. “But there’s just a lot of things internally that had happened over time, and it just got to a place where I don’t think it was good for me mentally. So, it is what it is. It happened and I’m moving forward.”

He spoke at the Nets' practice center, less than a week after the 76ers traded him to Brooklyn as part of a package for James Harden.

The former No. 1 overall pick hasn't played since the 76ers were beaten by Atlanta in Game 7 of the Eastern Conference semifinals. Postgame comments from teammate Joel Embiid and coach Doc Rivers after Simmons played poorly were considered the catalyst for his trade request, but Simmons said that wasn't the case.

“That was earlier than that series or even that season that I was dealing with and that organization knew that,” Simmons said. “So it’s something that I continue to deal with, and I’m getting there and getting to the right place to get back on the floor.”

Simmons said he hopes to be ready to play by the time the Nets visit the 76ers on March 10.

He thanked the 76ers organization and fans for their support and said he had spoken with some teammates and personnel — though not Embiid — after the trade. He also spoke that day with Kevin Durant, whom he will join along with Kyrie Irving in a lineup the Nets hope will be good enough to win the Eastern Conference.

“I think it’s going to be scary,” Simmons said. “Having those guys run alongside me, multiple different weapons on the floor and I think at the pace we want to play at, it’s going to be unreal.”

That was the expectation for his partnership with Embiid, the 76ers' All-Star center. They led Philadelphia to the best record in the East last season, but Simmons was already dealing with personal challenges he felt required him to leave the organization.

“I think I just wasn’t in the place there to do that and a lot of things had happened over that summer to where I didn’t feel like I was getting that help,” Simmons said. “But it is what it is. I don’t have any — it wasn’t a personal thing towards any player or coach or owners or anything like that. It was about myself, getting to a place where I need to be.”

He is happy so far in Brooklyn, where he was with the Nets on Monday when they beat Sacramento to snap an 11-game losing streak. Simmons didn't want to speak in depth about what he had been dealing with but was asked what he would say to those who saw him smiling at the game and don't believe his struggles were anything more than an excuse to seek a trade.

“They should be happy I’m smiling, honestly,” Simmons said. “I’ve had some dark times over the last six months and I’m just happy to be in this situation with this team and organization. So people are going to say what they want. They’ve said it the last six months and I haven’t commented and it is what it is, so people are always going to have their own opinions.”